While the older Raspberry Pi 3B and 3B+ models aren’t as powerful as the Pi 4 or new Pi 5, you may improve their performance by overclocking the CPU. This will make the processor run at a higher maximum speed, although you’ll need to find a way to dissipate the extra heat created to avoid CPU thermal throttling and maritain stability.
Follow the steps below to start overclocking your Raspberry Pi 3 and perform a stress test to check how it’s performing.
Why Overclock Your Raspberry Pi 3?
By overclocking your Raspberry Pi 3B from the standard 1.2GHz to up to 1.3GHz (or even higher), it should feel a little snappier while navigating the desktop GUI and you should see improved performance when running heavy workloads, such as when running aRaspberry Pi games system with RetroPie. You can also overclock the Pi 3B+ model from its default speed of 1.4GHz.
The downside to overclocking is that it could reduce the lifespan of your Pi 3B or 3B+. It may also void your warranty if you use theforce_turbo=1setting to enable turbo mode. So overclock at your own risk—especially if pushing it to higher speeds.
Keep It Cool to Avoid Throttling
One of the main things you need to consider when overclocking a Raspberry Pi 3B is the CPU temperature. If it rises above 80°C, the Raspberry Pi SoC has a safety mechanism that will automatically start throttling back the CPU cores, reducing their speed until the temperature drops. Maximum throttling, including of the GPU, occurs at 85°C.
On the Raspberry Pi 3B+, throttling kicks in at a mere 60°C, although you can push this up to 70°C with a configuration file setting. The Raspberry Pi 3B+ features a built-in heat spreader for its SoC, hence its silver color on the board. This enables the Pi 3B+ to have a higher default maximum CPU clock speed of 1.4GHz compared to the Pi 3B’s 1.2GHz. You can still add extra cooling, however.
As on other Raspberry Pi single-board computers (apart from the keyboard-integrated Pi 400), you can add passive cooling to the Pi 3B or 3B+ in the form of a heat sink attached to the SoC with thermal paste. SomeRaspberry Pi casesalso contain a built-in heat sink.
There’s also the option of active cooling in the form of a fan, powered by 5V or 3.3V. Again, some Pi cases have a fan built-in. Either cooling method, or both, will help to keep the CPU temperature down while running under heavy loads and at higher speeds when overclocking.
How to Overclock a Raspberry Pi 3
As with otherRaspberry Pi modelsrunning the official Raspberry Pi OS, you can alter the CPU’s clock speed by modifying theconfig.txtfile it uses for settings when booting up.
Before doing so, it’s a good idea to update and upgrade your system. Open a terminal window by clicking the icon in the top menu bar, or viaMenu > Accessories > Terminal, and entering:
Install Monitoring Tools
Before you overclock your Raspberry Pi 3B or 3B+, you’ll want to install a couple of useful tools to check its settings and how it’s performing. Firstly, install the Neofetch system info tool:
Next, install the Stressberry stress-testing tool:
To see the current system info, run:
It should show the default CPU speed of 1.2GHz on Pi 3B, or 1.4GHz on Pi 3B+. Before overclocking, you may want to perform an initial stress test at the default clock speed for comparison with the overclocked results later. Run this command for a 100-second test using all four CPU cores:
After awaiting a stable baseline temperature (which may take a while), it’ll start the stress test and each line will show the current CPU temperature and frequency (in MHz).
Edit the Config.txt File to Overclock
Now it’s time to change the CPU speed settings to start overclocking the Raspberry Pi 3B or Pi 3b+. Open theconfig.txtfile with the nano text editor:
Scroll down to find the section starting “#uncomment to overclock the arm” and delete the line below it. Note that this section may not be present in theconfig.txtfile of the Bookworm version of Raspberry Pi OS, but you may still add the lines below to overclock.
If you’re using a Pi 3B, add the following lines:
Here we’re raising the CPU maximum clock speed to 1.3GHz (up from 1.2GHz), the max core frequency to 500MHz (from 400MHz), and bumping up the GPU speed from 400MHz to 500MHz (optional). We are also increasing the core voltage level slightly (withover_voltage=4) and the SDRAM frequency to help improve performance.
If using a Pi 3B+, you’ll want to use the following settings instead:
Here we’re performing a modest overclock from the default 1.4GHz to 1.45GHz. The other lines remain the same as for the Pi 3B.
Now exit the nano text editor and save the new settings by pressingCtrl+X, thenYandEnter. To activate the overclock settings, you’ll need to reboot the Pi 3B or 3B+:
When the Pi reboots, run theneofetchterminal command again; you should see the new CPU speed that you set—in the case of the Pi 3B+, it’ll actually show 1.5GHz instead of 1.45GHz, but the latter is correct.
Stress-Test Your Overclocked Pi 3B/3B+
Let’s run the same stress test as before, using Stressberry:
This time you should see that the CPU reaches the overclocked speed of 1.3GHz (1300MHz), or 1.45GHz (1450MHz) on Pi 3B+. It will also have a higher temperature—in our tests, using a Pi 3B with no cooling, it rose to over 80° and the CPU started throttling until the temperature dropped. Adding cooling should help avoid or reduce this.
On a Pi 3B+ with no extra cooling, the temperature rose above 60° and throttling kicked in. If you want to increase this threshold on the Pi 3B+ to 70°C, add the following line toconfig.txtand reboot:
Overclocking Pi 3 to Higher Speeds
If you want to push the CPU speed of your Raspberry Pi 3B or 3B+ even higher, and maintain stability, you will definitely need a good cooling system. Note that to increase the overvoltage value to more than 6, you will also need to add the lineforce_turbo=1to theconfig.txtfile—this will void the warranty.
Some users have reported successfully overclocking the Pi 3B to 1.5GHz, and the Pi 3B+ up to an impressive 1.6GHz (using active and passive cooling), but your mileage may vary.
Pushing the speed to these kinds of heights is done at your own risk. If overclocking at a certain level causes system instability, you should attempt a more modest overclock or improve the Raspberry Pi’s passive/active cooling. In some cases, the Pi 3B/3B+ may not even boot up to the desktop.
What if the Raspberry Pi 3 Won’t Boot?
If, after changing the overclocking settings inconfig.txt, you find that your Raspberry Pi 3B/3B+ won’t boot up correctly, don’t fret. The simplest workaround is to hold theShiftkey during bootup to temporarily disable the overclock; the Pi should then boot up normally. you’re able to then reduce the overclock level that you set.
If it still won’t boot, you can always turn off the Raspberry Pi, remove the microSD card, and connect the latter (using a USB card reader) to another computer to edit theconfig.txtfile there. You can then alter the overclocking settings, or comment them out by adding a # symbol at the start of each line.
Raspberry Pi 3 Overclocking Is Easy
As shown above, overclocking your Raspberry Pi 3B or 3B+ is a relatively straightforward process. You may need to increase the overvoltage level at higher clock speeds, but it’s best not to push it past 12. Overclocking may also reduce the Pi’s lifespan.
With the extra processing power gained from overclocking, you the Pi should have ability to run other CPU-intensive tasks more effectively, including video playback and retro gaming. This will unlock more possibilities for how to use your Raspberry Pi.
